Pressure relief assembly

ABSTRACT

A thrust reverser of a nacelle may include an translating sleeve and an inner fixed structure a pressure relief assembly. A pressure relief mechanism may include a pressure relief door coupled via a hinge and a latch to the inner fixed structure. Alternatively, a pressure relief door may be coupled to a frame via a hinge and a latch to the inner fixed structure. The pressure relief assembly may limit deflections between the thrust reverser and the pylon in response to a burst duct. The pressure relief door may release from the latch automatically in response to an over pressurization event.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority to and the benefit of, provisionalpatent application No. 62/757,024, filed on Nov. 7, 2018 and entitled“PRESSURE RELIEF ASSEMBLY,” which is incorporated by reference herein inits entirety.

FIELD

The disclosure generally relates to turbofan propulsion systems for anaircraft. More particularly, the disclosure relates to pressure relieffor a nacelle for a turbofan propulsion system.

BACKGROUND

Modern aircraft may utilize one or more turbofan propulsion systemspowered by a gas turbine engine. The propulsion system may include anacelle, which is a system of components that house the engine and itsancillary systems, and help form aerodynamic surfaces for flight,including a fan bypass air duct. Often, the nacelle includes a thrustreverser. The thrust reverser includes an inner fixed structure (“IFS”)surrounding the engine which forms part of the interior surface of thebypass air duct through the thrust reverser. The volume between the IFSand the engine core defines the core compartment. In the corecompartment, there are high pressure, high temperature pneumatic ductsthat can fail, which would lead to catastrophic failure of the IFSstructure. In order to relieve this rapid pressurization, pressurerelief doors are provided that limit the pressure in the compartment toacceptable levels until the engine is shut down. Similar conditions canbe found in other compartments where high pressure pneumatic ducts arepresent.

SUMMARY

An aircraft nacelle is disclosed. The nacelle may comprise an innerfixed structure and a pressure relief assembly. The pressure reliefassembly may comprise a latch mechanism and a pressure relief door. Thelatch mechanism may comprise a pressure relief latch and be coupled tothe inner fixed structure. The pressure relief door may comprise abracket. The pressure relief latch may be configured to hold thepressure relief door in a fixed position.

In various embodiments, the pressure relief latch may be configured toautomatically release radially outward in response to an increase inpressure on the pressure relief door. The pressure relief door maycomprise a hinge coupled to the inner fixed structure. The pressurerelief mechanism may be located on the bottom portion of the inner fixedstructure. The thrust reverser may comprise a translating sleeve. Thepressure relief mechanism may be located aft of the translating sleeve.The latch mechanism may have a latch mechanism weight. The bracket mayhave a bracket weight. The bracket weight may be less than the latchmechanism weight. The inner fixed structure may be configured to bemounted to a thrust reverser of the nacelle.

A method of manufacturing a pressure relief arrangement is disclosed.The method may comprise fastening a latch mechanism to a frame. Theframe may comprise an aperture configured to receive a pressure reliefdoor. The aperture may have a first side and a second side opposite thefirst side. The latch mechanism may be fastened to the frame at thefirst side. The method may further comprise coupling a non-biased hingeto the frame at the second side of the aperture. The method may furthercomprise coupling the pressure relief door to the non-biased hinge. Thepressure relief door may comprise a bracket opposite the non-biasedhinge. The method may further comprise engaging the bracket with thelatch mechanism to hold the pressure relief door in a fixed position.

A method may further comprise installing the pressure relief arrangementon an inner fixed structure of a nacelle. Installing the pressure reliefarrangement may be done at an engine bottom location on the inner fixedstructure of the nacelle. Installing the pressure relief arrangement maybe done at a location aft of a translating sleeve on the inner fixedstructure of the nacelle. The bracket and latch mechanism may beconfigured to automatically release in response to an increase inpressure on the pressure relief door. The pressure relief door may beconfigured to hang down upon use providing an indication of use upon anaircraft landing.

A pressure relief arrangement is disclosed. The pressure reliefarrangement may comprise a frame, a latch mechanism, and a pressurerelief door. The latch mechanism may comprise a pressure relief latchcoupled to the frame. The pressure relief door may be coupled to theframe via a hinge. The pressure relief door may comprise a bracketconfigured to engage the pressure relief latch. The bracket may alsohold the pressure relief door in a fixed position relative to the frame.

In various embodiments, the frame may comprise mounting aperturesconfigured to mount the frame to a thrust reverser. The pressure reliefdoor and the frame may be separated by a gap at a position opposite thehinge. The bracket may have a bracket weight. The latch mechanism mayhave a latch mechanism weight. The bracket weight may be less than thelatch mechanism weight. The pressure relief door and the pressure relieflatch may be configured to disengage the bracket and release in the samedirection in response to increase in the pressure on the pressure reliefdoor. The frame may be configured to be welded to an inner fixedstructure of a nacelle.

BRIEF DESCRIPTION OF THE DRAWINGS

The subject matter of the present disclosure is particularly pointed outand distinctly claimed in the concluding portion of the specification. Amore complete understanding of the present disclosure, however, may bestbe obtained by referring to the detailed description and claims whenconsidered in connection with the drawing figures, wherein like numeralsdenote like elements.

FIG. 1 illustrates a perspective view of a nacelle in accordance withvarious embodiments of the disclosure;

FIG. 2 illustrates an aft view of a nacelle in a closed position inaccordance with various embodiments of the disclosure;

FIG. 3 illustrates an aft view of a nacelle in an open position inaccordance with various embodiments of the disclosure;

FIG. 4 illustrates a perspective view of a thrust reverser having apressure relief assembly in accordance with various embodiments of thedisclosure;

FIG. 5 illustrates a side view of a thrust reverser having a pressurerelief assembly in accordance with various embodiments of thedisclosure;

FIG. 6A illustrates a pressure relief assembly in accordance withvarious embodiments;

FIG. 6B illustrates a pressure relief assembly in accordance withvarious embodiments; and

FIG. 7 illustrates a perspective view of a thrust reverser having apressure relief arrangement in accordance with various embodiments ofthe disclosure;

FIG. 8 illustrates a side view of a thrust reverser having a pressurerelief arrangement in accordance with various embodiments of thedisclosure;

FIG. 9 illustrates a pressure relief arrangement in accordance withvarious embodiments;

FIG. 10 illustrates a method of use of nacelle pressure relief inaccordance with various embodiments.

FIG. 11 illustrates a method of manufacture of a pressure reliefarrangement installable on a thrust reverser in accordance with variousembodiments.

DETAILED DESCRIPTION

The detailed description of various embodiments herein makes referenceto the accompanying drawings, which show various embodiments by way ofillustration. While these various embodiments are described insufficient detail to enable those skilled in the art to practice theinventions, it should be understood that other embodiments may berealized and that logical, chemical and mechanical changes may be madewithout departing from the spirit and scope of the inventions. Thus, thedetailed description herein is presented for purposes of illustrationonly and not of limitation. For example, the steps recited in any of themethod or process descriptions may be executed in any order and are notnecessarily limited to the order presented. Furthermore, any referenceto singular includes plural embodiments, and any reference to more thanone component or step may include a singular embodiment or step. Also,any reference to attached, fixed, connected or the like may includepermanent, removable, temporary, partial, full and/or any other possibleattachment option. Additionally, any reference to without contact (orsimilar phrases) may also include reduced contact or minimal contact.

Systems for limiting deflections and stress in a nacelle with latchesare disclosed below in accordance with various embodiments. Duringflight, an engine duct may burst causing an increase in pressure insidea core compartment surrounding the engine, or other conditions mightexist which create a higher pressure inside of the core compartment thanoutside, resulting in a net force radially outward against the thrustreverser. Also, conditions might exist where a forward portion of thethrust reverser deflects outboard and begins to scoop the high velocityfan air stream in the bypass air duct, which can result in pressuresand/or forces difficult to control that challenge the continuedintegrity of the thrust reverser structure. Pressure relief doors may beemployed to prevent deflections of the thrust reverser structures.Proposed herein are pressure relief solutions which unlatchautomatically to provide pressure relief when it is needed to tend toprevent deflections of the thrust reverser structure and may provide anindication to grounds crews that an issue occurred during flight.

Referring to FIG. 1, a nacelle 100 for a gas turbine engine isillustrated according to various embodiments. Nacelle 100 may comprisean inlet 110, a fan cowl 120, and a thrust reverser 130. Nacelle 100 maybe coupled to a pylon 140, which may mount the nacelle 100 to anaircraft wing or aircraft body. Thrust reverser 130 may comprise aninner fixed structure (“IFS”) 132 and a translating sleeve 134. Bypassair from an engine fan may flow in a generally annular bypass air ductdefined between the IFS 132 and the translating sleeve 134. The IFS 132may be formed together with or be coupled to at its aft end a core cowl150, which in turn is adjacent to a nozzle 160 for core engine exhaustair. The thrust reverser 130 may further be split into a left half 136and a right half 138, such that there is, for example, a left half and aright half of IFS 132. The left half 136 and the right half 138 may behinged to the pylon 140 at hinges 170. The left half 136 and the righthalf 138 may hinge open at hinges 170 in order to provide access to theengine for inspection or servicing. The left and right halves of the IFS132 may together help form a core compartment around the engine when theleft and right halves 136, 138 of the thrust reverser are closed.

Referring to FIG. 2, an aft view of nacelle 100 in a closed position isillustrated according to various embodiments. Left half 136 and righthalf 138 of thrust reverser 130 may be split along split line 232.Engine fan 210 is visible through the bypass air duct between IFS 132and translating sleeve 134.

Referring to FIG. 3, an aft view of nacelle 100 with the thrust reverserhalves 136, 138 hinged open is illustrated according to variousembodiments. Thrust reverser halves 136, 138 and core cowl halves 352,354 are hinged open at hinges 170 in order to provide access to engine310.

Referring to FIG. 4, a perspective view of a thrust reverser having apressure relief assembly 420 is illustrated according to variousembodiments. For ease of reference, the translating sleeve of the thrustreverser is removed in the illustration. The pressure relief assembly420 may be coupled to the IFS 132. The pressure relief assembly 420 maybe located on the aft portion 414 of the IFS 132 to allow thepressurized fluid that builds up in a high pressure scenario, e.g., toprevent a burst duct scenario, to vent directly to ambient air. Thethrust reverser may comprise a translating sleeve forming the outer wallof the fan duct. The annular surface between the trailing edge of thetranslating sleeve and the inner fixed structure is the fan exit plane.The pressure relief mechanism may be located aft of the fan exit plane.

Referring to FIG. 5, a side view of a thrust reverser 130 having apressure relief assembly 420 is illustrated according to variousembodiments. The thrust reverser may comprise an translating sleeve 134forming the outer wall of the fan duct, an IFS 132, and a pressurerelief assembly 420. The annular surface between the trailing edge ofthe translating sleeve and the inner fixed structure is the fan exitplane. The pressure relief assembly 420 may be located aft of the fanexit plane. The pressure relief assembly 420 may be located anywhereradially on a nacelle. In an example embodiment, the pressure reliefassembly may be located on an engine bottom portion 516 of the IFS 132to allow the pressure relief assembly to release a greater volume offluid in a high pressure scenario, e.g., prior to a burst duct scenario.The engine bottom portion 516 is the bottom half of the thrust reverser130. This will ensure that upon use, the pressure relief assembly 420will open to ambient air. Additionally, when the pressure reliefassembly is on the engine bottom portion 516 of the IFS 132, thepressure relief assembly 420 may open after an event, which wouldprovide an indication that an event occurred based on visual inspectionafter an aircraft lands. Further, the pressure relief assembly 420 maycomprise a pressure relief door 522 and a relief hinge 524, about whichthe pressure relief door 522 opens when the pressure relief assembly 420is in use. The relief hinge 524 may be located at the forward edge ofthe pressure relief door 522 in order to ensure the pressure relief door522 remains open after use. The relief hinge 524 may couple the pressurerelief door 522 to the IFS 132 of the thrust reverser 130.

Referring to FIG. 6A, a pressure relief assembly 420 is illustratedaccording to various embodiments. The pressure relief assembly 420 maycomprise a latch mechanism 620 coupled to an IFS 132 of a thrustreverser, and a pressure relief door 522 comprising a bracket 632. Thelatch mechanism 620 may comprise a latch housing 626, a pressure relieflatch 622, and a fulcrum 624 about which the pressure relief latch 622pivots. The latch mechanism 620 may be coupled to the pressure reliefdoor 522 by engaging the pressure relief latch 622 to the bracket 632,fixing the pressure relief door 522 in place. The bracket 632 maycomprise a keeper 634 designed to fix the pressure relief latch 622 inplace during normal operation. The pressure relief door 522 may becoupled to the IFS 132 at a hinge located opposite the bracket 632, asshown in FIG. 5. The pressure relief door 522 and the IFS 132 may beseparated by a gap 602, where the latch mechanism 620 couples the IFS132 to the pressure relief door 522. In various embodiments, the gap 602may be sealed during normal operation. Since the latch mechanismcomprises several components, whereas the bracket may simply compriseattachment features and a keeper, the latch mechanism may besignificantly heavier compared to the bracket. Thus, by placing thebracket 632 on the pressure relief door 522, as opposed to placing thelatch mechanism 620 on the pressure relief door 522, the mass moment ofinertia of the pressure relief door 522 may be significantly reduced.This configuration results in a pressure relief door 630 that is able toopen more rapidly, relieving pressure faster, resulting in limited peakpressure during the burst duct event.

Referring to FIG. 6B, a pressure relief assembly 420 is illustrated inan open position. An open position occurs when a pressure differentialacross the pressure relief door 630 reaches or exceeds a predeterminedpressure threshold. The latch mechanism 620 may be configured toautomatically release the pressure relief latch 622 once the pressure onthe pressure relief door 522 reaches the predetermined pressurethreshold (trigger pressure). When in use, the pressure relief latch 622may pivot about the fulcrum 624 of the latch mechanism 620. The pressurerelief latch 622 may release outward of the IFS 132 of the thrustreverser and into ambient air. In an example embodiment, the pressurerelief 630 door may release automatically when the pressure reaches adefined pressure range. In an example embodiment the defined pressurerange may be 2-3.5 psid (13.79-24.13 kPa), depending on the design. Inanother example embodiment, the defined pressure range may be 2-5 psid(13.79-34.47). Once the pressure relief latch 622 releases the pressurerelief door 630, it will swing outboard relieving the pressure buildupin the compartment. The compartment pressure may peak as the pressurerelief door rotates outboard, but it may stabilize to a steady statepressure when the door reaches an equilibrium position.

Referring to FIG. 7, a perspective view of a thrust reverser having apressure relief arrangement 720 is illustrated according to variousembodiments. For ease of reference, the translating sleeve of the thrustreverser is removed in the illustration. The pressure relief arrangement720 may be coupled to the IFS 712. The pressure relief arrangement 720may be located on the aft portion 714 of the IFS 712 to allow thepressurized fluid that builds up in a high pressure scenario, e.g., aburst duct scenario, to vent directly to ambient air. The pressurerelief arrangement 720 may comprise a frame 722 and a pressure reliefdoor 724. The frame 722 may be coupled to the IFS 132 by welding,soldering or brazing the edges of the frame 722 to the IFS 132.Alternatively, the frame 722 may be coupled to the IFS 712 by standardfasteners, or any other mechanical fastening method known in the art.

Referring to FIG. 8, a side view of a thrust reverser having a pressurerelief arrangement 720 is illustrated according to various embodiments.The thrust reverser may comprise an translating sleeve 802, an IFS 712,and a pressure relief arrangement 720. The pressure relief arrangement720 may be located on an engine bottom portion 816 of the IFS 712 toallow the pressure relief arrangement to release a greater volume offluid in a high pressure scenario, e.g., a burst duct scenario. Thepressure relief arrangement 720 may be located aft of the translatingsleeve 802. This will ensure that upon use, the pressure reliefarrangement 720 will open to ambient air. Additionally, when thepressure relief arrangement 720 is on the engine bottom portion 816 ofthe IFS 712, the pressure relief arrangement 720 would remain open afteran event, which would provide an indication that an event occurred basedon visual inspection after an aircraft lands. Further, the pressurerelief mechanism may comprise a pressure relief door 724 and a reliefhinge 824, about which the pressure relief door 724 opens when thepressure relief arrangement 720 is in use. The relief hinge 824 may belocated at the forward edge of the pressure relief door 724 in order toensure the pressure relief door 724 remains open after use. The reliefhinge 824 may couple the pressure relief door 724 to the frame 722 ofthe pressure relief arrangement 720. The frame 722 may be coupled to theIFS 712 of the thrust reverser via mounting apertures 828. Any mountingmethod known in the art may be utilized. For example, the frame 722 maybe mounted to the IFS 712 by rivets, composite locks, screws, or anyother fastening method known in the art. Alternatively, the frame 722may be welded, soldered, or brazed to the IFS 712 without the use ofmounting apertures.

Referring to FIG. 9, a pressure relief arrangement 720 is illustratedaccording to various embodiments. The pressure relief arrangement 720may comprise a frame 722, a latch mechanism 920 coupled to the frame722, and a pressure relief door 724 comprising a bracket 932. The latchmechanism 920 may comprise a latch housing 926, a pressure relief latch922 and a fulcrum 924 about which the pressure relief latch 922 pivots.The latch mechanism 920 may be coupled to the pressure relief door 724by engaging the pressure relief latch 922 to the bracket 932, fixing thepressure relief door 724 in place. The bracket 932 may comprise a keeper934 designed to fix the pressure relief latch 922 in place during normaloperation. The pressure relief door may be coupled to the frame 722 at ahinge located opposite the bracket 932, as shown in FIG. 8. The pressurerelief door 724 and the frame 722 may be separated by a gap 902, wherethe latch mechanism 920 couples the frame 722 to the pressure reliefdoor 724. In various embodiments, the gap 902 may be sealed duringnormal operation. By placing the bracket 932 on the pressure relief door724, as opposed to placing the latch mechanism 920 on the pressurerelief door, the mass moment of inertia of the pressure relief door 724may be significantly reduced. This configuration results in a pressurerelief door 930 that is able to open more rapidly, relieving pressurefaster, resulting in limited peak pressure during the burst duct event.

Referring to FIG. 10, a method of use of relieving pressure in a corecompartment of an aircraft engine 1000 is illustrated according tovarious embodiments. The first step, block 1010, of relieving pressurein a core compartment comprises increasing a pressure in the corecompartment of an aircraft engine. This may occur during a high pressureengine scenario, and the intent is to prevent a duct in the engine frombursting due to the high pressure scenario. Without a pressure reliefarrangement, the IFS of a thrust reverser would need to be significantlystiffer to handle the structural loads of the pressure increase. Thesecond step, block 1020, is to release a pressure relief door coupled toa thrust reverser via a fixed latch and a hinge. Both the pressurerelief door and the fixed latch may release radially outward of thethrust reverser, as shown in FIG. 6B. The increased pressure is exertedon the latch that is fixed to the IFS as well as the pressure reliefdoor. The fixed latch may release the bracket that is coupled to thepressure relief door that results in an opening for a pressurized fluid,such as air, to escape. Referring back to FIG. 6B, this method mayresult in the pressure relief door 630 pivoting away from the fixedlatch. The third step, block 1030, of relieving pressure in a corecompartment may comprise reducing the pressure in the core compartmentbelow the predetermined threshold pressure. The pressure relief door maybe coupled to the thrust reverser by a non-biased hinge, so that thepressure relief door may remain open after an event. This may permit thepressure in the core compartment to be reduced below the predeterminedthreshold pressure. The pressure in the core compartment will eventuallyreach a steady state pressure below the predetermined threshold pressureand alleviating any potential structural damage to the aircraft engine.

Referring to FIG. 11, a method of manufacturing a pressure reliefarrangement installable on a thrust reverser of a nacelle 1100 isillustrated according to various embodiments. The first step, block 1110may comprise fastening a latch mechanism to a frame. The frame maycomprise an aperture configured to receive a pressure relief door. Thelatch mechanism may be placed along one side of the perimeter and hangover the edge of the aperture after block 1110. The second step, block1120 may comprise coupling a non-biased hinge to the frame at a sidelocation along the perimeter of the aperture and opposite the latch. Thenon-biased hinge and the latch mechanism may be fastened to frame byrivets, bolts, screws, or similar fastening methods known in the art.

The third step, block 1130, may comprise coupling a pressure relief doorto the non-biased hinge. The pressure relief door may comprise a bracketopposite the hinge attachment location. The fourth step, block 1140, maycomprise engaging the bracket coupled to the pressure relief door withthe latch mechanism from block 1110. Once engaged, the latch mechanismmay hold the pressure relief door in place. The latch mechanism andbracket may be configured to release once the pressure relief doorexceeds a specific pressure. After block 1140, the result may be apressure relief arrangement that may installable on various components.The fifth step, block 1150, may comprising installing the pressurerelief arrangement on an inner fixed structure of a thrust reverser. Thepressure relief arrangement may be installed by rivets, bolts, screws,or similar fastening methods. The pressure relief arrangement may beinstalled aft of the translating sleeve to ensure any escaping fluidreleases to ambient air. The pressure relief assembly may be installedon engine bottom to provide maintenance with an indication if thepressure relief arrangement was used during a previous flight.

In the detailed description herein, references to “one embodiment”, “anembodiment”, “various embodiments”, etc., indicate that the embodimentdescribed may include a particular feature, structure, orcharacteristic, but every embodiment may not necessarily include theparticular feature, structure, or characteristic. Moreover, such phrasesare not necessarily referring to the same embodiment. Further, when aparticular feature, structure, or characteristic is described inconnection with an embodiment, it is submitted that it is within theknowledge of one skilled in the art to affect such feature, structure,or characteristic in connection with other embodiments whether or notexplicitly described. After reading the description, it will be apparentto one skilled in the relevant art(s) how to implement the disclosure inalternative embodiments.

Benefits, other advantages, and solutions to problems have beendescribed herein with regard to specific embodiments. Furthermore, theconnecting lines shown in the various figures contained herein areintended to represent various functional relationships and/or physicalcouplings between the various elements. It should be noted that manyalternative or additional functional relationships or physicalconnections may be present in a practical system. However, the benefits,advantages, solutions to problems, and any elements that may cause anybenefit, advantage, or solution to occur or become more pronounced arenot to be construed as critical, required, or essential features orelements of the inventions. The scope of the inventions is accordinglyto be limited by nothing other than the appended claims, in whichreference to an element in the singular is not intended to mean “one andonly one” unless explicitly so stated, but rather “one or more.”Moreover, where a phrase similar to “at least one of A, B, or C” is usedin the claims, it is intended that the phrase be interpreted to meanthat A alone may be present in an embodiment, B alone may be present inan embodiment, C alone may be present in an embodiment, or that anycombination of the elements A, B and C may be present in a singleembodiment; for example, A and B, A and C, B and C, or A and B and C.Different cross-hatching is used throughout the figures to denotedifferent parts but not necessarily to denote the same or differentmaterials.

Furthermore, no element, component, or method step in the presentdisclosure is intended to be dedicated to the public regardless ofwhether the element, component, or method step is explicitly recited inthe claims. No claim element herein is to be construed under theprovisions of 35 U.S.C. 112(f) unless the element is expressly recitedusing the phrase “means for.” As used herein, the terms “comprises”,“comprising”, or any other variation thereof, are intended to cover anon-exclusive inclusion, such that a process, method, article, orapparatus that comprises a list of elements does not include only thoseelements but may include other elements not expressly listed or inherentto such process, method, article, or apparatus.

We claim:
 1. A nacelle comprising: an inner fixed structure; a pressurerelief assembly comprising: a latch mechanism comprising a pressurerelief latch coupled to the inner fixed structure; a pressure reliefdoor comprising a bracket, the pressure relief latch configured to holdthe pressure relief door in a closed position.
 2. The nacelle of claim1, wherein the pressure relief latch is configured to automaticallyrelease radially outward in response to an increase in pressure on thepressure relief door.
 3. The nacelle of claim 1, wherein the pressurerelief door comprises a hinge, the hinge coupled to the inner fixedstructure.
 4. The nacelle of claim 1, wherein the pressure reliefassembly is located on a bottom portion of the inner fixed structure. 5.The nacelle of claim 1, further comprising an translating sleeve,wherein the pressure relief assembly is located aft of the translatingsleeve.
 6. The nacelle of claim 1, wherein the latch mechanism has alatch mechanism weight and the bracket has a bracket weight, wherein thebracket weight is less than the latch mechanism weight.
 7. The nacelleof claim 1, wherein the inner fixed structure is configured to bemounted to a thrust reverser of a nacelle.
 8. A method of manufacturinga pressure relief arrangement, the method comprising: fastening a latchmechanism to a frame comprising an aperture configured to receive apressure relief door, the aperture having a first side and a second sideopposite the first side, and the latch mechanism being fastened to theframe at the first side; coupling a non-biased hinge to the frame at thesecond side of the aperture; coupling the pressure relief door to thenon-biased hinge, the pressure relief door comprising a bracket oppositethe non-biased hinge; engaging the bracket with the latch mechanism tohold the pressure relief door in a fixed position.
 9. The method ofmanufacturing of claim 8, the method further comprising installing thepressure relief arrangement on an inner fixed structure of a nacelle.10. The method of manufacturing of claim 9, wherein the installing thepressure relief arrangement is done at an engine bottom location on theinner fixed structure of the thrust reverser.
 11. The method ofmanufacturing of claim 9, wherein the installing the pressure reliefarrangement is done at a location aft of a translating sleeve on theinner fixed structure of the nacelle.
 12. The method of manufacturing ofclaim 8, wherein the bracket and the latch mechanism are configured toautomatically release in response to an increase in pressure on thepressure relief door.
 13. The method of manufacturing of claim 10,wherein the bracket and the latch mechanism are configured toautomatically release in response to an increase in pressure on thepressure relief door.
 14. The method of manufacturing of claim 10,wherein the pressure relief door is configured to hang down upon useproviding an indication of use upon an aircraft landing.
 15. A pressurerelief arrangement comprising: a frame; a latch mechanism comprising apressure relief latch coupled to the frame; and a pressure relief doorcoupled to the frame via a hinge, the pressure relief door comprising abracket configured to engage the pressure relief latch and hold thepressure relief door in a fixed position relative to the frame.
 16. Thepressure relief arrangement of claim 15, wherein the frame comprisesmounting apertures configured to mount the frame to a nacelle.
 17. Thepressure relief arrangement of claim 15, wherein the pressure reliefdoor and the frame are separated by a gap at a position opposite thehinge.
 18. The pressure relief arrangement of claim 15, wherein thebracket has a bracket weight and the latch mechanism has a latchmechanism weight, wherein the bracket weight is less than the latchmechanism weight.
 19. The pressure relief arrangement of claim 18,wherein the pressure relief door and the pressure relief latch areconfigured to disengage the bracket and release in the same direction inresponse to increase in the pressure on the pressure relief door. 20.The pressure relief arrangement of claim 15, wherein the frame isconfigured to be welded to an inner fixed structure of a nacelle.